Massive volumes of GPS trajectory data bring challenges to storage and processing. These issues can be addressed by compression algorithm which can reduce the size of the trajectory data. A key requirement for GPS trajectory compression algorithm is to reduce the size of the trajectory data while minimizing the loss of information. Synchronized Euclidean distance (SED) as an important error measure is adopted by most of the existing algorithms. In order to further reduce the SED error, an improved algorithm for open window time ratio (OPW-TR) called local optimum open window time ratio (LO-OPW-TR) is proposed. In order to make SED error smaller, the anchor points are selected by calculating point’s accumulated synchronized Euclidean distance (ASED). A variety of error metrics are used for the algorithm evaluation. The experimental results show that the errors of our algorithm are smaller than the existing algorithms in terms of SED and speed errors under the same compression ratio

The traditional text similarity measurement methods based on word frequency vector ignore the semantic relationships between words, which has become the obstacle to text similarity calculation, together with the high-dimensionality and sparsity of document vector. To address the problems, the improved singular value decomposition is used to reduce dimensionality and remove noises of the text representation model. The optimal number of singular values is analyzed and the semantic relevance between words can be calculated in constructed semantic space. An inverted index construction algorithm and the similarity definitions between vectors are proposed to calculate the similarity between two documents on the semantic level. The experimental results on benchmark corpus demonstrate that the proposed method promotes the evaluation metrics of F-measure.

Indexing

JIPS is also selected as the Journal for Accreditation by NRF (National Research Foundation of Korea).

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Society

ABOUT THE SOCIETY

Ever since information processing became one of the most important industries in the country, computing professionals have encountered a growing number of challenges.
Along with scholars and colleagues in related fields, they have gathered together at a variety of forums and meetings over the last few decades to share their knowledge and experiences,
and the outcomes of their research. These exchanges led to the founding of the Korea Information Processing Society (KIPS) on January 15, 1993. The KIPS was registered as an incorporated association under the Ministry of Science,
ICT and Future Planning under the government of the Republic of Korea. The main purpose of the KIPS organization is to improve our society by achieving the highest capability possible in the domain of information technology.
As such, it focuses on close collaboration with the nationâs industry, academic, and research communities to foster technological innovation,
to enhance its members' careers, and to promote the advanced information processing industry.